In 1980 we began a prospective study of the health effects of "subclinical" malnutrition in a group of 270 healthy elderly individuals. These subjects were recruited in 1979 and were at least 65 years of age, in good health, and taking no prescription medication. Nutritional status was evaluated yearly by clinical exam, three-day diet record, and biochemical parameters. Health status was determined by a yearly physical exam and review of private physician and hospital records. In addition, the relationship between nutritional status and immunological function was studied in this population. The primary goal of this five year renewal is to continue the study until there is sufficient mortality and/or total number of morbid events to allow a meaningful analysis of the relationship between nutritional status and subsequent mortality and morbidity. Age related changes in nutritional status will also be investigated in this group through the yearly nutritional evaluation. We will continue the yearly clinical evaluation, three-day diet record, and biochemical determinations of proteins, lipids, vitamins and minerals. New high performance liquid chromatographic techniques will be implemented for measurement of vitamins A, E, B6, and C including dehydroascorbic acid. A new test for biotin by competitive radioimmunoassay and a new assay for thiamine will be implemented. Two controlled studies will be initiated. One to measure plasma and mononuclear cell levels of ascorbic acid, dehydroascorbic acid and ascorbic free radical at controlled intakes of ascorbic acid. The second will be a trial of vitamin supplementation to investigate effects on lipid levels (total, LDL and HDL cholesterol, and triglycerides) and immune function. The study of the effect of life crises on nutritional status will also be continued.